title: Magnetic resonance spectroscopy and molecular studies in ornithine transcarbamylase deficiency novel mutation c.802A>G in exon 8 (p.Met268Val).
abstract: Ornithine transcarbamylase (OTC) deficiency, an X-linked, semidominant disorder, is the most common inherited de-fect in ureagenesis, resulting in hyperammonaemia type II. The OTC gene, localised on chromosome X, has been mapp-ed to band Xp21.1, proximate to the Duchenne muscular dystrophy (DMD) gene. More than 350 different mutations, including missense, nonsense, splice-site changes, small de-letions or insertions and gross deletions, have been describ-ed so far. Almost all mutations in consensus splicing sites confer a neonatal phenotype. Most mutations in the OTC gene are 'private' and are distributed throughout the gene with a paucity of mutation in the sequence encoding the leader peptide (exon 1 and beginning of exon 2) and in exon 7. They have familial origin or occur de novo. Even with sequencing of the entire reading frame and exon/intron boundaries, only about 80% of the mutations are detected in patients with proven OTC deficiency. The remainder probably occur within the introns or in regulatory domains. The authors present a 4-year-old boy with the unreported missense mutation c.802A>G. The nucleotide transition leads to amino acid substitution Met to Val at codon 268 of the OTC protein.
authors.affiliation: Klinika Pediatrii i Neurologii Wieku Rozwojowego, Śląski Uniwersytet Medyczny, ul. Medyków 16, 40-752 Katowice, Polska.
authors.forename: E
authors.initials: E
authors.lastname: Jamroz
authors.forename: J
authors.initials: J
authors.lastname: Paprocka
authors.forename: M
authors.initials: M
authors.lastname: Sokół
authors.forename: E
authors.initials: E
authors.lastname: Popowska
authors.forename: E
authors.initials: E
authors.lastname: Ciara
mesh_terms: D002675:Child, Preschool; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009154:Mutation; D009954:Ornithine Carbamoyltransferase / Q000235:genetics*; D020163:Ornithine Carbamoyltransferase Deficiency Disease / Q000175:diagnosis* / Q000235:genetics*
chemical_list: D009954:Ornithine Carbamoyltransferase